摘要
对珠三角典型土壤(潮土和水稻土)加入一系列硝酸钙、氧化钙和碳酸钙进行室内培养,采用连续化学提取方法对原土及添加上述成分后各种形态氟进行提取,并采用极谱测定方法进行检测,研究各形态的转化行为。试验结果表明:加入氧化钙和碳酸钙可使两种土壤pH值明显上升,有利于改善土壤酸性;但使两种土壤有效态氟(水溶态氟、可交换态氟)含量上升,而铁锰结合态氟总体下降。故氧化钙不适用于该类高氟土的酸性改良,而碳酸钙的适用性则由土壤理化性质决定。硝酸钙的加入使各形态氟含量均呈下降趋势,在施用剂量大于20 mg/25 g时,对土壤中有效态氟有较好的抑制作用,但对土壤酸化没有改善。
The soil of Zhujiang Delta was investigated by the test method using polarography, which included fluvo-aquic soil and paddy soil. The total fluorine and the species of fluorine in original soil and the cultivated soil were determined with sequential extraction. The species of fluorine were transformed before and after adding calcium nitrate, calcium oxide and calcium carbonate. Though pH of soil was increased and the soil could be prevented from acidification after adding calcium oxide and calcium carbonate, it would improve the leaching of bioavailability fluoride （water soluble fluoride and exchangeable fluoride）, and the fluoride bound to Fe/Mn oxides was reduced. Calcium oxide does not apply to the acidic improvement of such high fluoride soil, but the applicability of calcium carbonate mainly depend on the soil physical and chemical nature. The addition of calcium nitrate makes all forms of fluoride showing a downward trend, and when the amount of the additive is more than 20 mg/25 g doses, the effective state of the soil has good fluoride inhibition, but no improvement in soil acidification.
出处
《广州化学》
CAS
2009年第4期13-18,30,共7页
Guangzhou Chemistry
基金
"广东省珠江三角洲经济区农业地质与生态地球化学调查"专题项目(1212010511216)
关键词
氟
钙肥
fluorine
calcium
